Taipei, Thursday, August 28, 2014 23:55 (GMT+8)
Linear announces synchronous buck LED driver controller
Michael McManus, DIGITIMES, Taipei [Monday 29 October 2012]

Linear Technology recently announced the LT3763, a synchronous buck LED driver controller that delivers over 300W of LED power. Its 6V to 60V input voltage range satisfies a wide variety of applications, including automotive, industrial and architectural lighting. Similarly, its output voltage can be set from 0V to 55V, enabling it to drive a wide range of LEDs in a single string.

The LT3763 offers both input and output current monitors and limiting, which accurately control both input and output current. Similarly, the LT3763 also offers accurate output voltage regulation as well as input regulation, useful for high impedance sources such as solar panels. Its constant current and constant voltage regulation makes it ideal for applications ranging from driving high brightness LEDs to battery and supercap charging. Additionally, True Color PWM dimming capability offers dimming ranges as wide as 3,000:1 for LED applications. The LT3763 is unique design utilizes four control loops to monitor input current, LED /output current, output and input voltage to deliver optimum performance and reliability.

The LT3763 uses two external switching MOSFETs and can deliver from 5W to over 300W of continuous LED power with efficiencies up to 96%. LED current accuracy of +6% ensures constant lighting while + 1.5% output voltage accuracy offers several LED protection features and also enables the converter to operate as a constant voltage/constant current source for charging applications. The LT3763 can utilize either analog or PWM dimming as required by the application. Furthermore, its switching frequency can be programmed between 200kHz and 1MHz or synchronized to an external clock. Additional features include open/short protection, C/10 detection, input and output current monitors, and integrated fault protection.

The LT3763EFE is available in a 28-lead thermally enhanced TSSOP package, priced starting at US$4.45 each, in 1,000-piece quantities. An extended temperature version, or I grade, the LT3763IFE, is also available, priced starting at US$4.90 each in 1,000-piece quantities.